EP0073290A2 - Installation and process for the recuperation of hydrocarbon products from used oils - Google Patents

Abstract

The invention relates to an installation for recovering hydrocarbon products from used oils or the like by mechanical/thermal reprocessing, in particular by distillation and/or rectification. The installation consists of equipment items such as evaporators, a condensation column, heating and cooling elements, heat exchangers, pumps, filters etc. The items are combined in a small, especially transportable functional unit, which preferably is designed to be mobile. In particular, the evaporator is heated electrically, either inductively or by resistance elements. The required electrical energy is taken either from the local mains or, with particular advantage, is produced by a diesel generator which is rigidly joined to the functional unit. Its waste heat is advantageously used for preheating the used oil. <IMAGE>

Description

The invention relates to a plant and a method for obtaining hydrocarbon products from waste oils or the like. by mechanical / thermal processing, in particular by distillation or rectification.

It is known to regenerate used oil on an industrial scale to obtain lubricating oils. Here, impurities are first separated off using filters and / or centrifuges, then acid components and possibly long-chain hydrocarbon components, which have arisen as a result of aging of the oil and which would reduce its lubricating power and would cause corrosion if the oil were used again, are then chemically removed or eliminated.

A disadvantage of the regeneration of waste oils for the extraction of lubricating oils is, on the one hand, the relatively high outlay for the recovery of qualified lubricating oils, which impairs the economic viability of such processes, and on the other hand, that the quality of the regenerated lubricating oil cannot be exactly predetermined due to the uncontrollable composition of the waste oil. Another disadvantage is that the lubricity of an originally highly qualified lubricant is irreversibly deteriorated in every reprocessing process. For the above reasons, in practice, waste oils and their mixtures have already been processed in plants in the petrochemical industry for the production of hydrocarbon products. However, since this only makes economic sense in refineries and only on an industrial scale, petrochemical processing requires a great deal of organizational and financial effort, except in special cases, to collect the waste oil via a network of collection points Transporting and storing used oil processing plants and bringing the volume into line with the capacity of a large petrochemical processing plant and keeping it in line.

In practice, it turned out that the treatment of waste oil almost always failed due to organizational difficulties in collecting and collecting the relatively small amounts that were generated in a large number of places. So far, this has meant that large quantities of old oils were not reused, but either burned or otherwise destroyed to the detriment of the environment.

The object of the invention is to provide a plant and a method for the economical production of hydrocarbon products from waste oils or the like. to be made available, which, with the avoidance of larger collection organizations and facilities, allows the waste oil to be processed in an environmentally friendly manner at the point of occurrence or at decentralized small collection points to obtain high-quality fuels and / or valuable other petrochemical products.

The object is achieved according to the invention by a system comprising units, such as pumps and, if appropriate, vacuum pumps, filters, evaporators, condensation columns, heating and cooling elements, heat exchangers, measuring and control devices, containers, lines, etc., in which the units are small, especially portable Form functional unit.

In a departure from previous ideas, a system in the form of a small, preferably transportable functional unit can surprisingly also be used economically to process used oil or the like. immediately at the place of the attack or at decentralized small collection points.

In an embodiment of the system according to the invention it is provided that the functional unit is designed to be mobile. This increases the mobility of the system to such an extent that it can be moved from one place to another with the least possible technical and / or financial outlay and is ready for operation immediately after reaching the place of use without cost or time for reaching production readiness .

In a further embodiment of the invention, in order to further improve mobility, an embodiment is provided in which the units are compactly combined to protect against transport damage and are preferably arranged in a rigid container-like frame. In order to create the optimal conditions for this purpose, an appropriate design further provides that the units or housings and frames accommodating them are designed with essentially rectangular contours with flat boundary surfaces, their fastening elements preferably the bottom surface and their connecting and / or connecting elements preferably the top surface assigned. This configuration advantageously results in the best conditions for the installation of the units in the container-like frame and a spatial arrangement in the smallest space is possible without the clarity of the system suffering. Furthermore, the stability of the functional unit is further increased by the box-shaped design of the individual units. In addition, the assembly or replacement of individual units for the purpose of revision or repair is made easier, which significantly increases the availability of the system.

In a further embodiment of the invention it is provided that the functional unit is equipped with an operating and control station which is arranged on the outside of the preferably container-like frame. Through a The operating and control center can easily and simply monitor the individual functions of the system and be controlled entirely or partially automatically. An arrangement on the outside ensures optimum clarity and ease of use,

In a further embodiment of the invention, it is provided that the evaporator preferably has an electrical heating device, for the energy requirement of which a power generation unit is provided in particular. With this configuration, the system is advantageously characterized by a universal usability that is independent of the power grid. Especially with the planned frequency of the change of location, this has the advantage of being completely independent of the connection values of existing power connections and the system is ready for operation at any time without difficulty and without the existing networks being overloaded. In this way, the advantages of an electrical heating device, which leads to a particularly quick operational readiness of the system and enables particularly good controllability of the system, can be fully exploited.

In a further embodiment of the invention, it is provided that the functional unit and the power generation unit are connected to one another on a common base frame to form a transport unit, and that the transport unit has, in particular, a chassis or is placed on one. This results in an easily transportable, portable system that eliminates the need to set up waste oil collection points and can be used wherever waste oil occurs without delay.

In a further embodiment of the invention, it is provided that the electrical heating device is designed as an induction heating device. An induction heater is Particularly advantageous for the system according to the invention, since the heat required is generated directly in the steel jacket of the evaporator, so that the waste oil is heated up very quickly. No heating elements need be arranged in the interior of the evaporator, so that maintenance is particularly simple and no corrosion problems can occur on heating elements.

In a further embodiment of the invention, it is provided that the electrical heating device is designed as an electrical resistance heater, which preferably has heating elements arranged around or in the evaporator. Resistance heating elements are available by the meter and only need to be provided with insulation if they are arranged on the outside of the evaporator or with a corrosion protection layer if they are arranged in the evaporator. This results in a particularly inexpensive version of the evaporator heating.

It is envisaged that the heating resistors in ceramics, glass or the like. are cast in and are preferably arranged vertically. This results in a corrosion-proof design of the heating elements, the vertical arrangement having the particular advantage that the individual heating rods are always at least partially immersed in the waste oil in the lower part of the evaporator and cannot overheat.

In another embodiment of the invention it is provided that the evaporator preferably has oil or gas heated heating coils arranged on its outside. Heating with gas or oil makes it possible to use the valuable materials generated in the system during distillation or rectification to heat the evaporator. This then advantageously results in a system whose electrical energy requirement is very low and is based on electrical energy for the measuring and control devices, ventilators ren etc. limited. In such a system, a power generation unit can generally be dispensed with, since any normally secured power socket is sufficient as an electrical connection.

In a further embodiment of the invention it is provided that an internal combustion engine is provided for driving the power generating unit, a heat exchanger preferably being connected to the exhaust gas line of the internal combustion engine and, if appropriate, a further heat exchanger for heating the waste oil connected to the coolant circuit thereof. This configuration further improves the economy of the system, particularly with regard to the energy requirement. In an internal combustion engine, for example a diesel engine, approximately 70% of the primary energy fed in is normally lost to the environment through heat losses. Because the vast majority of the waste heat from the internal combustion engine is transferred to the waste oil by heat exchangers in connection with the system according to the invention, these heat losses are avoided and the otherwise lost heat is made usable for the treatment. Since the exhaust gases occur at a temperature of 800 ° C, if the heat flows are appropriately matched, for example when the waste oil is preheated in a continuous pass through a first heat exchanger arranged in the coolant circuit and a second heat exchanger connected to the exhaust line, preheating can be carried out up to Temperatures over 200 ° C take place. Only the increase in temperature up to evaporation and the heat of vaporization must be applied by the electrical heating device or the oil or gas-heated heating coils.

It is provided that power consumers, such as pumps, fans, actuators and / or switching elements, lighting devices etc. are connected to an electrical network which is permanently installed in the container-like frame are, which is also connected on the input side to the power generation unit. The result is a system that is completely independent of the power grid when an electric heater is selected.

In carrying out the process for the recovery of hydrocarbon products from waste oils or the like. the system according to the invention provides that the waste oil or waste oil mixture is mixed and diluted with portions of the product obtained and processed or prepared in a mixture or dilution. This procedure has the particular advantage that the filtration capacity of the viscous waste oil is significantly improved, so that the filtering preceding the distillation or rectification can be carried out using commercially available, relatively small-pore filters. The distillation capability and thus the product quality are also positively influenced and the performance of the relatively uncomplicatedly constructed portable system is increased. Furthermore, an adjustment to very different waste oil qualities is possible with the same product quality.

In a further embodiment of the invention it is provided that the distillation or rectification is carried out under excess pressure. This results in an advantageous boiling point increase and an advantageous considerable reduction in the size of the individual units on the gas side, so that the system as a whole can be downsized.

In a further embodiment of the invention, it is finally provided that the process is carried out at a temperature and a pressure which are, for example, between 400 ° C. and 800 ° C. and 1 to 4 bar, in particular approximately 420 ° C. and 1.5 bar , so that at least cracking of the long-chain hydrocarbon molecules takes place. As a result, the output of valuable materials is advantageously increased considerably and the proportion of those in the evaporator sump remaining very long-chain hydrocarbons reduced. An analysis showed that the distillate obtained in accordance with the invention fulfills all the requirements that have to be met for the usability as heating oil or diesel fuel. The non-usable residues that are periodically removed from the evaporator, with overpressure operation ensuring particularly good emptying, are only approx. 5%.

The invention is explained in more detail below with reference to drawings, which show particularly preferred exemplary embodiments and from which further advantageous details can be found.

• Fig. 1 eine fahrbare Anlage in einem containerartigen Gestell mit Stromerzeugungsaggregat in Seitenansicht,
• Fig. 2 die Anlage gemäß Fig. 1 in einer Sicht von hinten,
• Fig. 3a-3d die Anordnung der Aggregate in dem containerartigen Gestell in Ansicht von hinten, von rechts und von vorn,
• Fig. 4 ein containerartiges Gestell,
• Fig. 5 ein schematisch dargestellter Verdampfer mit induktiver Beheizung im Schnitt,
• Fig. 6 das Unterteil eines schematisch dargestellten Verdampfers mit Gas-oder ölbeheizung und äußerer Isolierung,
• Fig. 7 eine Teilansicht eines schematisch dargestellten Verdampfers mit eingehängten Widerstandsheizelementen,
• Fig. 8 einzelne Widerstandselemente,
• Fig. 9 die Anordnung von Widerstandselementen in einem horizontalen Verdampfer,
• Fig. 10 die schematische Darstellung von Widerstandsheizelementen oder Heizspiralen in einem Ringheizelement,sowie
• Fig. 11 die schematische Ansicht eines vertikalen Verdampfers mit Widerstandsheizelementen, die zu einem mit dem Deckel verbundenen Heizelementbündel zusammengefaßt sind.

The drawings show in detail:

• 1 is a mobile system in a container-like frame with a power generator in side view,
• 2 the system of FIG. 1 in a view from behind,
• 3a-3d the arrangement of the units in the container-like frame in a view from behind, from the right and from the front,
• 4 a container-like frame,
• 5 is a schematically illustrated evaporator with inductive heating in section,
• 6 the lower part of a schematically represented evaporator with gas or oil heating and external insulation,
• 7 is a partial view of a schematically shown evaporator with suspended resistance heating elements,
• 8 individual resistance elements,
• 9 shows the arrangement of resistance elements in a horizontal evaporator,
• Fig. 10 is a schematic representation of resistance heating elements or heating spirals in a ring heating element, as well
• Fig. 11 is a schematic view of a vertical evaporator with resistance heating elements, which are combined to form a heating element bundle connected to the cover.

The mobile transport unit 1 in Fig. 1 comprises the actual plant 3 for the production of hydrocarbon products, the power generating unit 2 and the chassis 4. The latter is a conventional single-axle chassis, as is customary, for example, for attaching to a car. However, the system can also be mounted on a small truck, so that a towing vehicle is not required.

The illustration shows the compact, space-saving transportable design of the entire unit. The power generation unit 2 takes up the largest space, while the actual extraction system 3 in the container-like frame 5 takes up much less space. A common base frame 4 'connects the actual system 3 and the power generation unit 2 to form a transport unit.

Fig. 2 shows the view of the mobile transport unit 1 in a view from behind. This illustration also clearly shows the size relationships on the one hand of the actual extraction system 3 and on the other hand of the power generation unit 2 in connection with the chassis 4.

The arrangement of the units belonging to the distillation plant in the container-like frame 5 is shown in FIGS. 3a to 3d. The following units can be seen in FIG. 3a, which shows the container-like frame 5 in a view from the rear: the evaporator 6 with heating elements 7 and the column 8 arranged above it. The heating elements 7 are electrical heating elements. A level controller 9 ensures that the filling level of the liquid to be evaporated is always constant inside the evaporator 6. The expansion device 10 is connected to the column 8 and to this the cooler 11 with attached heat exchanger 12. Another heat exchanger 13, which connects to the exhaust pipe of the internal combustion engine Power generator 2 can be connected, the heat exchanger 12 is connected downstream. The distillation system 3 further comprises a third heat exchanger 14 and a filter unit 15. The illustration in FIG. 3a shows in a convincing manner the advantageous interrelation between the design of the units and / or the housing and / or frames receiving them, which essentially have rectangular contours have flat boundary surfaces. As a result, an extremely compact spatial division with the best possible clarity is achieved. Furthermore shows the advantageous design of the units through the possibility of arranging the fastening elements 16 preferably on their bottom surfaces, which, with extremely little use of assembly work, enables the units to be optimally fastened in the individual fastening levels 17, 18 and 19.

The further constructive measure which is essential for the invention, namely the arrangement of the connection and / or connecting elements 20 on the top surfaces of the units or at least the upper region thereof, has a similarly advantageous effect.

3b shows the system 3 according to the invention in a view from the right. The arrangement of the evaporator 6 together with the column 8 is clearly visible. Next to it is a compressor 23 which forms an aggregate unit with the heat exchanger 24.

An aggregate unit 21, consisting of a gas trap with a pump and pressure vessel, is fastened on the upper fastening level 19. The fastening elements 16 of the units are clearly recognizable on their respective underside, as are the connection and / or connecting elements 20 in the area of the top surfaces. The number 22 denotes an absorber. This illustration also shows the clear, space-saving and compact arrangement of the individual units achieved within the container-like frame 5 achieved by the special configuration according to the invention.

3c shows the same system unit 3 according to the invention in a view from the left and thus the arrangement of the cooler 11. Next to it is a pump unit 25, including the filter 15 and to the right next to it the prefilter 26. On the lower fastening level 17 there is also a separator 30 and a pump unit 31 arranged and with attached their fasteners 16. The two filters 27 and 28 and an associated pump unit 29 are arranged in an intermediate fastening level 17 '. The fastening elements 16 are also each arranged on their underside, whereas the connection and / or connecting elements 20 are located on their top surfaces.

Fig. 3d shows the system 3 according to the invention in a view from the front and thus the switch panel 32, which is arranged above a sheet metal casing 33. The illustration in FIG. 4 gives an impression of the structure of the container-like frame 5. It shows a perspective view of the fastening levels 17, 18 and 19, and also a fan unit 34 belonging to the cooler 11. The frame 5 is advantageously welded together and made of profiles 35 the sides covered with formwork sheets 37. The top is formed by a perforated plate 36. For better access to individual units, this is inserted into U-profiles 38 and fixed therein.

Fig. 5 shows the schematically illustrated evaporator, which consists of two parts 40 and 41. A flange connection is provided between the two parts 40 and 41, a sealing washer 42 being arranged between the flanges. The container part 40 is surrounded by induction coils 43, which can be cooled by the coolant lines 44. The coolant in the lines 44 can also advantageously be used for preheating the used oil to be treated or the like. be used. In the bottom of the container 40 there is a discharge opening 45 through which the residues which cannot be distilled or rectified are withdrawn periodically.

6 shows the heating of the lower container part 46 by means of gas or oil-heated heating coils 48, which have insulation 47 on their outside. For further Insulation of the evaporator is provided with an outer insulation in sandwich construction, which consists of two cover layers 50a and 50b and the insulating material 49 arranged between them. This sandwich insulation is regularly provided, without being shown in all representations, in order to reduce the heat consumption of the evaporator.

Fig. 7 shows a section of an evaporator wall 51 in a vertical arrangement with hanging heating elements 52. The hanging arrangement has the advantage that the heating elements are at least partially immersed in the bath even with a sinking bath level and thus the heating elements are prevented from drying out with certainty.

Fig. 8 shows various heating elements, which are designed either as screw or insert elements in the bottom, in the lid or in the side walls of the evaporator. The heating coils 53, 58 and 61 are each embedded in ceramic or glass 54, 57 or 60, in particular molded in and connected to the lid, the bottom or the side walls of the evaporator via screw connections 55, plug connections 56 or combined screw and plug connections 59. A particularly advantageous ceramic material is Al 0, which is not only corrosion-resistant, but also acts as a catalyst. In particular, it increases the proportion of petrol in the fuel produced.

Fig. 9 shows the arrangement of heating elements in vertical evaporators. It is both possible to distribute them in the lower part of the evaporator in accordance with the heating elements 65, so that the entire volume of the lower part of the evaporator is heated uniformly by the heating elements. In the same way, it is also possible to arrange the heating elements in a ring shape on the evaporator wall 62, in particular wide heating elements 63 with a large number of heating conductors, which are likewise cast in ceramic or glass or molded in can be used. This results in a relatively large free space in which a real cooking process can take place with a good swirling of the used oil. The heating-up time is somewhat longer compared to the arrangement with the distributed heating elements 65, but the distillation is somewhat more advantageous.

10 shows an arrangement with heating spirals 67 in the hollow wall of a ring heating element 66 in the evaporator 69. With this arrangement, a completely corrosion-protected arrangement of the heating spirals 67 in the ring 66 can advantageously be achieved, so that the heating elements 67 are not poured in or molded in can. Repairs to the heating coil are possible. The heating spirals 67 are accommodated in the cover 68 and can be lifted out of the ring heating element 66 by lifting off the cover 68.

Another arrangement of the heating elements 72 in the evaporator 70 is shown in FIG. 11. Here, the heating elements 72 are combined to form a brush-like unit which can be lifted out together with the cover 71. The result is a particularly easy-to-use cover-heating element unit that allows simple replacement of heating elements and is particularly suitable for vertical evaporators.

The invention is not limited to the types of heating shown and to the arrangement of the individual units shown in the functional unit. Without departing from the scope of the invention, the individual units can be arranged differently within the functional unit and other types of heating can be selected. The examples shown represent a particularly favorable selection.

Claims (17)

1. Plant for the extraction of hydrocarbon products from waste oils or the like. by mechanical / thermal processing, in particular by distillation or rectification, comprising units, such as pumps and, if appropriate, vacuum pumps, filters, evaporators, condensation columns, heating and cooling elements, heat exchangers, measuring and control devices, containers, lines, etc., characterized in that the units (6 to ₁₅ , 21 to 31) form a small, in particular transportable functional unit (3). 2 Plant according to claim 1, characterized in that the functional unit (3) is mobile. 3. Installation according to one of claims 1 or 2, characterized in that the units (6 to 15, 21 to 31) are compactly assembled and are preferably arranged in a rigid, container-like frame (5). 4. Plant according to one of claims 1, 2 or 3, since = characterized in that the units (6 to 15, 21 to 31) and / or housing or frames receiving them are designed with substantially rectangular contours with flat boundary surfaces, the Fastening elements (16) are preferably assigned to the bottom surface and their connection and / or connecting elements (20) are preferably assigned to the top surface. 5. Plant according to one of claims 1, 2, 3 or 4, characterized in that the functional unit (3) is equipped with an operating and control center (32) which is arranged on the outside of the preferably container-like frame (5). 6. Plant according to one of claims 1, 2, 3, 4 or 5, characterized in that the evaporator (6) preferably has an electric heating device (7), for whose energy requirements in particular a power generation unit (2) is provided. 7. Plant according to one of claims 1, 2, 3, 4, 5 or 6, characterized in that the functional unit (3) and the power generating unit (2) on a common base frame (4 ') to a transport unit (1) connected to each other are and that the transportable unit (1), in particular a chassis (4) or is placed on such. 8. Plant according to claim 6, characterized in that the electrical heating device (7) is designed as an induction heating device. 9. Plant according to claim 6, characterized in that the electric heating device (7) is designed as an electrical resistance heater, which preferably has heating elements arranged around or in the evaporator (6). 10. Plant according to claim 6, 7 or 9, characterized in that the electrical heating device (7) in ceramic, glass or the like. Has cast-in heating resistors (53, 58, 61) for heating, which are preferably arranged vertically in the interior of the evaporator (6). 11. Plant according to one of claims 1 to 5, characterized in that the evaporator (6) preferably arranged on its outside oil or gas heated heating coils (48). 12. Plant according to claim 6 or 7, characterized in that an internal combustion engine is provided for driving the power generating unit, preferably connected to the exhaust pipe of the internal combustion engine, a heat exchanger (13) and optionally to its coolant circuit, a further heat exchanger (12) for heating the waste oil is. 13. Plant according to one of the preceding claims, characterized in that power consumers such as pumps (21, 29, 31), fans (34) actuating and / or switching elements, lighting devices etc. connected to a fixed in the container-like frame (5) electrical network are, which is connected on the input side to the power generation unit (2). 14. Process for the recovery of hydrocarbon products from waste oils or the like. with a system according to at least one of the preceding claims, characterized in that the waste oil or waste oil mixture is mixed and diluted with portions of the product obtained and processed or prepared in a mixture or dilution. 15. Process for the recovery of hydrocarbon products from used oils or the like. with a plant according to at least one of the preceding claims, characterized in that the distillation or rectification is carried out in stages, with different valuable substances being drawn off in the individual stages. .16. A method according to claim 14 or 15, characterized in that the distillation or rectification is carried out under excess pressure. 17. The method according to claim 14, 15 or 16, characterized in that it is carried out at a temperature and a pressure, e.g. between 400 ° C and 800 ° C and 1 to 4 bar, especially at about 420 ° C and 1.5 bar, so that at least partially the long-chain hydrocarbon molecules are cracked.

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